31. CYPRIXID.E ORTnODON. 151 



nearly terete, its lengtli contained 4f times in the length of the body, its 

 least depth 2j in its length. Uead moderate, 4^ in length of body, 

 bliintish, the profile considerably rounded, the iuterorbital space 

 strongly convex. Mouth horizontitl, subinferior, overlapped by the 

 broad, blunt snout, its breadth considerable, but the maxillary not ex- 

 tending far back, to opposite the front of the eye. Upper jaw pro- 

 tractile, covered with a fleshy lip, inside of which is a small, straight, 

 cartilaginous plate, similar to that on the lower jaw, but much smaller 

 and not evident externallj'. Lower lip covered with a firm cartilagi- 

 nous plate, sharp externally, the upper surface being formed by its 

 bevelled edge. The transverse width of this plate is between four and 

 five times its (longitudinal) breadth. The plate extends in nearly a 

 straight line from one angle of the mouth to the other ; its transverse 

 width is contained 2^ times in the length of the head. Eye rather 

 large, 5^ in head. If in snout, its position anterior and not high up, 2^ 

 in iuterorbital space. Dorsal long, rather low, its first ray just behind 

 the first ray of ventrals, midway between the snout and the middle of 

 the base of the caudal fin. Caudal fin very long, the lobes about equal, 

 longer than the head, widely forked, the accessory rays at is base very 

 luimerous and recurrent on the caudal peduncle ; about eight of these 

 may be distinguished on each side of the fin. Anal fin rather large; 

 ventrals broad, reaching vent. Pectorals moderate, not reacliing two- 

 thirds of the distance to the ventrals. Scales quite small, somewhat 

 imbedded in the skin, very loosely imbricated, or ofteu scarcely imbri- 

 cated at all, the exposed surfaces longer than high, profusely punc- 

 tate; squamation quite irregular; the scales smaller on back and belly 

 than on sides, most exposed on caudal peduncle. Lateral line much 

 decurved. Coloratioa very dark, belly paler, but nearly all parts of the 

 body studded with minute dark points. D. 10; A. 9; scales 20-85- 

 10. Teeth 4-5, hooked, somewhat club-shaped, with a broad mas- 

 ticatory surface. Peritoneum black ; intestines nuich elongate, filled in 

 this specimen with vegetable substance. L. 12 inches. Columbia Eiver 

 and tributaries. 



(Agassiz, Amer. Jonrn. Sci. Arts, xix, 214, LS-'o ; Glinthcr, vii, 276; Jordan. Proc. U. 

 S. Nat. Mus. i, 83, lti7b,) 



■ya.— ORTIIOI[>0.\ Girard. 



(Girard, Proc. Acad. Nat. Sci. Pliila. 1850, 183: typo Gila microhnndota Ayres.) 



Body elongate. Jaws normal, the upper protractile, the lower sharp- 

 edged, with a knob at the symphysis ; no barbel. Teeth 0-0 or 0-5, 



